Geopolymers vs. Cement Matrix Materials: How Nanofiller Can Help a Sustainability Approach for Smart Construction Applications—A Review

Abstract

In the direction of reducing greenhouse emissions and energy consumption related to the activities of the cement and concrete industry, the increasingly popular concept of eco-sustainability is leading to the development and optimization of new technologies and low impact construction materials. In this respect, geopolymers are spreading more and more in the cementitious materials field, exhibiting technological properties that are highly competitive to conventional Portland concrete mixes. In this paper, the mix design, mechanical properties, microstructural features, and mineralogical properties of geopolymer mixes are discussed, investigating the influence of the main synthesis parameters (curing regime, type of precursors, activator molarity, mix design) on the performance of the final product. Moreover, recent developments of geopolymer technology based on the integration of functional nanofillers are reported. The novelty of the manuscript is to provide a detailed collection of past and recent comparative studies between geopolymers and ordinary Portland concrete mixes in terms of strength properties, durability, fire resistance, and environmental impact by LCA analysis, intending to evaluate the advantages and limitations of this technology and direct research towards a targeted optimization of the material.

Reducing the emission of climate-altering substances in cementitious materials: A comparison between alkali-activated materials and Portland cement-based composites incorporating recycled tire rubber

“…Taking the results of the OPC mixtures as reference values, it is possible to note ECO2 reduction rates close to 30% and 40% for Control-AAM and RP100-AAM mixes, respectively. This finding aligns well with the results reported in a previous review work conducted by the authors (Valente et al, 2021), in which it was found that the AAM technology represents a valid eco-sustainable solution to ordinary cement mixes, bringing on carbon emissions reduction rates up to 80%. For both matrices, an increase in the carbon footprint was estimated by replacing the mineral fraction with the tire rubber aggregate.…”

Nano-Silica-Modified Concrete: A Bibliographic Analysis and Comprehensive Review of Material Properties

“…Utilizing resources economically and effectively has become a priority nowadays. Cement, being the primary component of concrete, has been under criticism in recent decades for the amount of CO 2 emitted during its manufacture [1][2][3]. While cement possesses superior mechanical characteristics, it has been unable to meet the standards of durability [4][5][6][7].…”

Development of a Commercial Screed Mortar with Low OPC Content by Incorporation of Biomass Fly Ash

“…Other supplementary cementitious materials can possess hydraulic activity, meaning that they can chemically react with water, set and harden [11]. FA have also been used with success in the development of alkali-activated binders [12][13][14][15] a topic that as gaining increasing interest for the development of more sustainable building materials [13][14][15] alternatives to those based on OPC [14,15].…”